Refrigerating apparatus with condenser lint burner



Sept. 3, 1963 R. E. GOULD 3,102,395

REFRIGERATING APPARATUS WITH CONDENSER LINT BURNER Filed Jan. 15, 1962 2Sheets-Sheet l Fig. 2

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United States Patent 3,1tl2,395 REFRIGERATENG APPARATUS WITH CONDENSER ILHNT BURNER Richard E. Gouid, Dayton, Ohio, assignor to General MotorsCorporation, Detroit, Mich a corporation of Delaware Filed Jan. 15,1962,Ser. No. 166,206 2 Claims. (El. 62155) This invention relates torefrigerating apparatus and particularly to a part of the refrigeratingsystem thereof.

It is known that a condenser, especially a compact aircooled condenserof the finned tube type, of a refrigerant translating device of arefrigerating system catches foreign substances, such as lint and dustparticles commingled with and carried by air circulated over and throughthe condenser, thereon which gradually accumulates as a mass of fuzz orthe like intermediate fins and tubes thereof to such a degree as toeventually clog or block passageways between parts of the condenser andair cannot be flown therethrough and over portions thereof for coolingsame. Consequently, the effectiveness of the condenser to cool andcondense refrigerant received therein from the re frigerant translatingdevice of the refrigerating systern is reduced or minimized, thusimpairing the efficiency of the refrigerating system to an extent thatthe refrigerant evaporator of the system will be prevented from loweringthe temperature in a refrigerated zone or chamber of a refrigeratorcabinet to a predetermined desired low temperature. This necessitates acall to a refrigeration service establishment which requires a serviceman to make a trip to the refrigerator installation and remove, bybrushing and/or blowing, the accumulation of foreign substances frompassageways in the condenser to restore the efficiency of therefrigerating system. These service calls are quite frequent in someinstances and they are annoying and expensive. I contemplate theelimination of such service calls by an arrangement that will at alltimes throughout use of the refrigerating system maintain airpassageways over and through parts of the refrigerant condenser thereoffree of dust and lint accumulations.

An object of my invention is to provide an improved refrigeranttranslating device of a refrigerating system of a refrigeratingapparatus.

Another object of my invention is to provide means in a refrigeratingsystem for periodically and automatically removing foreign substancesfrom the refrigerant condenser'of a refrigerant translating device ofthe system whereby to prevent accumulation thereof thereon so that itsoriginal effectiveness and a predetermined efficiency of therefrigerating system will be maintained throughout prolonged use of arefrigerator cabinet or refrigerating apparatus with which the system isassociated.

A further object of my invention is to provide means for stopping anddepositing thereon lint commingled with and carried by air circulatedtoward a condenser of a refrigerating system and for consuming the lintby burning it therefrom.

In carrying out the foregoing objects, it is a still further and morespecific object of my invention to provide an artificially heated grilleelement in front of and in the path of air circulated over an air cooledcondenser of a refrigerant translating device of a refrigerating systemupon which lint and other foreign substance is lodged or accumulatedprior to reaching the condenser and to periodically and automaticallyrender the heater of the grille element effective or to energize samefor igniting the lint or foreign substance to consume it and cause itsremoval therefrom.

Further objects and advantages of the present invention will be apparentfrom the following description, refer- "ice ence being had to theaccompanying drawings wherein a preferred embodiment of the presentinvention is clearly shown.

In the drawings:

FIGURE'I is a view diagrammatically showing a refrigerating system of arefrigerating apparatus having my 7 invention embodied therein;

FIGURE 2 is an enlarged front view of a heated grille element disposedin the path of air circulated toward the air cooled refrigerantcondenser of the refrigerating system shown in FIGURE 1; 7

FIGURE 3 is an enlarged fragmentary sectional view taken on the line 33of FIGURE 2 showing wires of the grille element, at least some of whichare electrical resistance wires;

FIGURE 4 is a fragmentary sectional view taken on the line 4-4 of FIGURE3 also showing wires of the grille element;

FIGURE 5 is a fragmentary sectional view taken on the line 55 of FIGURE3 showing the spaced apart and crossed arrangement of the grille elementwires; and

FIGURE 6 is a wiring diagram for controlling the refrigerating systemand the heater of the grille element associated with the condenserthereof.

Referring to the drawings, for illustrating my invention, I show inFIGURE 1 thereof a refrigerating system which maybe employed in ahousehold refrigerator cabinet or which may be employed to cool a zoneor chamber in any other type of refrigerating apparatus. Prior todescribing the present invention, I wish it to be understood that therefrigeratin-g system herein disclosed is preferably adaptedfor use in arefrigerating apparatus or cabinet of the character more fullyillustrated and described in the copending application of L. J. Mann andI. J. OConnell, Serial No. 116,224, filed May 9, 1961, now Patent No.3,050,961, and assigned to the assignee of this application. Referenceis made to this copending application so as to simplify the presentdisclosure and maintain the description herein brief to my invention.The refrigerating system shown in FIGURE 1 of the drawings comprises arefrigerant evaporator 11, a refrigerant translating device 12 includingan air-cooled refrigerant condenser 13 and conduits connecting theevaporator, device 12 and condenser 13 in closed refrigerant flow orcirculating relationship. Condenser 13 is preferably of the typeincluding coiled tubing 14 and a plurality of fins 16 (see FIGURE 3)mount-ed thereon for increasing heat transference from the tubing. An

electric motor 17 drives a fan or blower 18 which forcibly V circulatesair over the condenser 13. The refrigerant translating device l2includes, in addition to condenser 13, a casing containing an electricmotor operatively connected to a refrigerant compressor also containedor sealed in the casing as is conventional in the art. Operation of themotor and compressor within casing 12 of the device causes evaporationor vaporization of refrigerant in evaporator ll, to cool air in achamberor compartment (not shown) in which the evaporator is located, and thisevaporated refrigerant is drawn into the compressor and compressedthereby and the compressed refrigerant is forced into condenser 13.Motor 17 is energized simultaneously with the compressor motor andoperates fan 18 to flow air over condenser 13 for cooling and liquefyingrefrigerant received in the condenser from the compressor.Liquidrefnigerant is admitted, byway of a restrictor or expansion valve(not shown), to evaporator 11 for reevaporation therein as is well knownto those skilled in the art. The air moving means or fan 18 causesforeign substances, such as dust and lint commingled with and carried byair in a room or the like in which the refrigerator cabinet orrefrigerating apparatus containing the refrigerating system is located,to be circulated toward the refrigerant condenser 13. This lint anddust, if not prevented from contacting condenser 13, is deposited onparts thereof or is lodged in passageways therethrough and anaccumulation thereof on the condenser will, in time, clog and block airpassages through the condenser and impair or minimize its effectivenessto condense refrigerant therein which results in a reduction inefiiciency of the refrigerating system.

According to my invention, I provide a means cooperating with anddisposed in front of condenser 13 in the path of air circulated by fan18 toward same for catching and accumulating thereon foreign substances,such as dust and'lint, carried by the circulating air which isperiodically energizable or rendered effective to consume the foreignsubstances caught or accumulated on the means so as to maintain thecondenser free thereof whereby its effec- Y tiveness is not impaired.This means is preferably a component part of the condenser 13 and is ofa character that will periodically and automatically ignite and burn anyaccumulation of lint thereon so as to consume the lint. Thus, I mount,in any suitable or desirable fashion, a screen a grille element,generally represented by the reference numeral 24) in FIGURE 1 of thedrawings, on the forward or' air incoming side of condenser 13. Grilleelement 20 comprises a frame 21 which is telescoped over and secured toa'bounding member 22 on the con- I denser 13 so as to form a componentpart thereof (see FIGURES). The four walls of frame 21 of element 20each have a metal strip 24 secured by rivets or the like to the innerface thereof and each strip 24 is provided with a plurality ofspning-tensioned fingers 26 projecting therefrom and spaced from frame21. Each spaced apart finger 26 carriers a grooved ceramic or the likeinsulator 27 and a wire is located in the groove of these insulators.The screen or grille element 20 is composed of a vertical continuouspiece of wire 28 and a horizontal continuous piece of wire 29. Runs orloops of the vertical wire 28 are parallel and all of them are in thesame plane with one another and the runs or loops of horizontal wire 29are also parallel and disposed in the same plane with one another.Parallel vertical wires 28 are in a difierent plane than horizontalwires 29 and are spaced a small distance behind the vertical wires toform the screen or grille. It should be understood that, for the purposeof illustrating my invention, only one set of the wires 28 or 29 may besuflicient and would be less expensive. However, in consideration of allcontingencies, :both of the sets of vertical and horizontal wires 28 and29 respectively are shown in this disclosure. wires 28 and 29 may beelectrical resistance wires in series in each set and provided at endsthereof with an insulated terminal connector indicated at 31 in FIGURES1 and 2 secured to bounding frame 21 of the screen or grille element 20.In the present disclosure, only the vertical wires 28 are electricallyenergizabls to provide a heater associated with the grille or screenelement 20*.

The terminal connectors 31 have conductor wires 32.

and 33 attached thereto and these conductor wires are connected to asource of electric current supply as will be hereinafter describedrelative to FIGURE-6 of the drawings and in respect to the explanationof automatically emergizing and deenergizing a set of the heater wiresof element 20. Heater wire 28 is tightly strung, wound or coiled aboutthe spring fingers 26 to place these fingers under tension at all timesso as to compensate for expansion of the wires 28 when heated andcontraction thereof when cooled.

Referring now to FIGURE 6 there is shown a wiring diagram for therefrigerator cabinet or apparatus with which the refrigerating systemherein disclosed is to be associated. An electric current supplyconductor 41 is connected through a starting relay 42 with thecompressor motor 43, within casing 12, of the motor compressor unit. Thestarting relay 42 controls the flow of current through a phase winding44 of the motor 43. Also connected to One or both sets ofthe supplyconductor 41 is the motor 17 of fan 18 which is connected in parallelwith the motor 43 and in series with a thermostat 46 which is responsiveto temperatures produced by evaporator 11 to control starting andstopping of compressor motor 43. The thermostat 46 is connected to acontact 47 of a double throw switch 48 controlled by a timer motor or anelectrical ehronornetric device 49 for effecting defrosting ofevaporator 11. Periodically, say, for example, once each day, the doublethrow switch 48 is moved, by timer 4-9, to close switch 48 into contactwith a stationary terminal 51 thereof. The switch 43 as well as thedefrost timer 49 are connected to a second electric current supplyconductor 52. When the defrost timer 49 operates to move switch 48 awayfrom contact orterminal 47 into contact with the terminal or contact 51,a defrost period or cycle of the refrigerating system is initiated torid evaporator 11 of frost or ice. This deenergizes the motors 17 and 43to discontinue the refrigerating effect of evaporator 11 and to stopcirculating of air by fan 18 over the condenser 13. It energizes aheater 53 through a normally closed defroster limiter thermostat 54associated with evaporator 111 to heat and defrost same. The heating ofevaporator 11 continues a sufiicient length of time to melt frost or icetherefrom. Heating of evaporator 11 is terminated when the defrostlimiter thermostat 54 reaches a sufficiently high temperature, saybetween and E, which indicates the condition insuring completion of thedefrosting. When this temperature is reached, the limiter thermostat S4-is opened. The resistance heater wire 28 of screen or grille element 20is connected in parallel with defroster heater 53 and is simultaneouslyenergized therewith to ignite and consume any foreign substance, such aslint, caught by and accumulated on the screen or grille element byburning it therefrom. This once a day energization of heater 28 insuresthat air passageways through the refrigerant condenser 13 will bemaintained open and free for flow of air therethrough or over tions-hipwith motor 17 so as the condenser. While I have illustrated the lintburner 28 as being energized or rendered effective every twentyfourhours, it is to be understood that the same may be energized in anyother suitable or desirable fashion to consume accumulated lint morefrequently or periodically throughout longer periods of time. Whenlimiter thermostat 54 opens, an electromagnet 56 in a shunt circuitaround the limiter thermostat is energized and operates the double throwswitch 48 back to its normal position in contact with terminal 47 sothat refrigeration produced by the refrigerating system will be resumedsince the switch 46 will be closed by the warmer conditions ofevaporator 11 prevailing during the defrost period. In the event thatthe defroster limiter switch 54 fails to operate, the switch 48 will bereturned to its normal position by the defrost timer t9. Ilf the presentrefrigerating system is employed in a household refrigerator cabinet ofthe type disclosed in the copending application hereinbefore identified,a fan and a motor for driving same to circulate cool air within chambersof the cabinet will be included in the system with such fan motorconnected in parallel relato be simultaneously energized therewith.

From the foregoing, it should be apparent that I have provided animproved refrigerating system wherein, regardless of the amount ofair-borne foreign substance or lint carried by air circulated over thecondenser thereof, the effectiveness of the condenser is not minimizedand the emciency of the refrigerating system remains at a desired highcapacity throughout prolonged usage of the system. By periodically andautomatically energizing a heating means associated with the grilleelement cooperating with the condenser of the refrigerating system inresponse to use of the system, no lint can accumulate on components ofthe refrigerant condenser and the same therefore never has to bemechanically cleaned. I, therefore, eliminate service calls whileinsuring continued use of a refrigerating system at its original maximumefiiciency. Since my invention provides for igniting and burning lint orother air-borne foreign substances froma condenser or a component partthereof at least once each day, there is no excessive amount of fuzzthereon at any time to emit odors sufficient to be objectionable andhazards incident to the burning process are thereby avoided.

While the embodiment of the present invention, as herein disclosed,constitutes a preferred form, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. A refrigerating system comprising in combination:

(a) a refrigerant evaporator, a refrigerant translating device includinga refrigerant condenser and conduits connecting said evaporator, saiddevice and said condenser in closed refrigerant flow relationship,

(b) means for cycling said refrigerant translating device automatically,

(c) air moving means effective during effectiveness of the device forcirculating air over said condenser to cool refrigerant received thereinfrom said device,

(d) means for maintaining said condenser free of foreign substancescommingled with and carried by the air circulated toward same,

(2) said last-named means including a grille secured to said condenserand providing a permanent component thereof,

(1) said grille having spaced-apart lengths of electrical resistancewire paralleling the front of said condenser in the path of aircirculated thereto,

(g) said wires forming the sole means of catching and accumulatingthereon the foreign substances circulating with said air, and

(h) means actuated by said cycling means for energizing and deenergizingsaid wires to consume the foreign substances accumulated thereon byburning it during an 01f [cycle of said translating device.

2. A refrigerating system comprising in combination:

(a) .a refrigerant evaporator, a refrigerant condenser, a motor, acompressor and conduits connecting said evaporator, said condenser andsaid compressor in closed refrigerant flow relationship,

(b) means intermittently energizing said motor automatically in responseto refrigeration demands imposed on said evaporator for operating saidcompressor,

(0) air moving means effective during operation of said compressor forcirculating air over said condenser to cool refrigerant received thereinfrom said compressor,

(d) a first heater connected to a source of electric current supply fordefrosting said evaporator,

(e) air filtering means for said condenser disposed in the path of :aircirculated toward same for catching and accumulating foreign substancescornmingled with and carried by the air,

(f) said filtering means including a second heater connected to saidsource of electric current supply,

and

(g) means actuated periodically rendering said firstnamed meansinefiective and simultaneously energizing both of said heaters fordefrosting said evaporator and for consuming the foreign substancesaccumulated on said air filtering means respectively by burning it whilethe evaporator is being defrosted.

References Cited in the file of this patent UNITED STATES PATENTS839,797 Wood Dec. 25, 1906 2,226,444 Caulk Dec. 24, 1940 2,780,924Latter Feb. 12, 1957 2,810,267 Renter Oct. 22, 1957 2,811,840 ThompsonNov. 5, 1957 3,001,295 Miller Sept. 26, 1961 FOREIGN PATENTS 620,906Great Britain Mar. 31, 1949

1. A REFRIGERATING SYSTEM COMPRISING IN COMBINATION: (A) A REFRIGERANTEVAPORATOR, A REFRIGERANT TRANSLATING DEVICE INCLUDING A REFRIGERANTCONDENSER AND CONDUITS CONNECTING SAID EVAPORATOR, SAID DEVICE AND SAIDCONDENSER IN CLOSED REFRIGERANT FLOW RELATIONSHIP, (B) MEANS FOR CYCLINGSAID REFRIGERANT TRANSLATING DEVICE AUTOMATICALLY, (C) AIR MOVING MEANSEFFECTIVE DURING EFFECTIVENESS OF THE DEVICE FOR CIRCULATING AIR OVERSAID CONDENSER TO COOL REFRIGERANT RECEIVED THEREIN FROM SAID DEVICE,(D) MEANS FOR MAINTAINING SAID CONDENSER FREE OF FOREIGN SUBSTANCESCOMMINGLED WITH AND CARRIED BY THE AIR CIRCULATED TOWARD SAME, (E) SAIDLAST-NAMED MEANS INCLUDING A GRILLE SECURED TO SAID CONDENSER ANDPROVIDING A PERMANENT COMPONENT THEREOF, (F) SAID GRILLE HAVINGSPACED-APART LENGTHS OF ELECTRICAL RESISTANCE WIRE PARALLELING THE FRONTOF SAID CONDENSER IN THE PATH OF AIR CIRCULATED THERETO,